Vintage authentication technology for aged Baijiu: Acid-ester equilibrium

This paper investigates a Baijiu vintage authentication technology based on the acid-ester equilibrium principle, providing a comprehensive analysis of its technical foundation, application outcomes, advantages. Research confirms that the aging process of Baijiu constitutes a dynamic acid-ester equilibrium system. As aging progresses, the liquor gradually approaches a state of thermodynamic equilibrium, with the equilibrium constant (K) stabilizing. By measuring the reaction quotient (Q) of ester compounds in the liquor and comparing it with the equilibrium constant (K), the aging status of Baijiu can be objectively and accurately evaluated, thereby enabling vintage authentication. Findings demonstrate the technology's strong universality across various aroma types and alcohol concentrations of Baijiu. Regardless of whether it is strong-aroma (<i>Nong</i>), sauce-aroma (<i>Jiang</i>), or other aroma types, or whether it is high-alcohol or low-alcohol Baijiu, the evolution patterns of acid-ester equilibrium remain consistent and effectively reflect the liquor's aging extent. The vintage prediction tool developed based on this technology has demonstrated outstanding performance in test cases, accurately categorizing Baijiu of different aging periods into corresponding vintage ranges, validating its practical application value.